Corporate Indebtedness - Junior Subordinated Deferrable Interest Debentures and Principal Maturities (Details)	1 Months Ended
Jun. 30, 2005 USD ($) quarter	Jun. 30, 2023 USD ($)
Principal Repayments and Joint Venture Debt
Remaining 2023		$ 263,076,000
2024		962,237,000
2025		470,000,000
2026		0
2027		1,980,000,000
Thereafter		150,000,000
Total principal repayments		3,825,313,000
Trust Preferred Securities
Debt Instrument [Line Items]
Proceeds from issuance of debt	$ 100,000,000
SOFR \| Trust Preferred Securities
Debt Instrument [Line Items]
Interest rate added to base rate (as a percent)	0.26%
Interest payment deferment, number of consecutive quarters \| quarter	8
Joint venture
Principal Repayments and Joint Venture Debt
Remaining 2023		527,899,000
2024		1,299,626,000
2025		1,604,151,000
2026		362,137,000
2027		1,189,059,000
Thereafter		2,130,404,000
Total principal repayments		7,113,276,000
Joint venture \| Trust Preferred Securities
Principal Repayments and Joint Venture Debt
Remaining 2023		0
2024		0
2025		0
2026		0
2027		0
Thereafter		100,000,000
Total principal repayments		100,000,000
Joint venture \| Mortgages and other loans payable
Scheduled Amortization
Remaining 2023		2,927,000
2024		4,488,000
2025		0
2026		0
2027		0
Thereafter		0
Total amortization of debt		7,415,000
Principal Repayments and Joint Venture Debt
Remaining 2023		260,149,000
2024		332,749,000
2025		370,000,000
2026		0
2027		550,000,000
Thereafter		0
Total principal repayments		1,512,898,000
Joint venture \| Revolving Credit Facility
Principal Repayments and Joint Venture Debt
Remaining 2023		0
2024		0
2025		0
2026		0
2027		430,000,000
Thereafter		0
Total principal repayments		430,000,000
Joint venture \| Unsecured Term Loans
Principal Repayments and Joint Venture Debt
Remaining 2023		0
2024		625,000,000
2025		0
2026		0
2027		1,000,000,000
Thereafter		50,000,000
Total principal repayments		1,675,000,000
Joint venture \| Senior Unsecured Notes
Principal Repayments and Joint Venture Debt
Remaining 2023		0
2024		0
2025		100,000,000
2026		0
2027		0
Thereafter		0
Total principal repayments		$ 100,000,000

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